From Superhydrophilicity to Superhydrophobicity: Laser-Induced Wettability Control of 7075 Aluminum via Chemical-Free Surface Texting and Air Ageing

From Superhydrophilicity to Superhydrophobicity: Laser-Induced Wettability Control of 7075 Aluminum via Chemical-Free Surface Texting and Air Ageing | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article From Superhydrophilicity to Superhydrophobicity: Laser-Induced Wettability Control of 7075 Aluminum via Chemical-Free Surface Texting and Air Ageing Zhang Wei, Li Xiaoyu, Wang meilin, Chen Hao This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9544139/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study presents a reagent-free route to engineer robust superhydrophobicity on 7075 aluminum alloy substrates through fiber laser surface texturing. Uniform parallel microgroove arrays were inscribed using a fiber laser marking system at optimized parameters (8 W power, 10-50 mm/s scan speed, 20 kHz repetition frequency, 0.05 mm focal spot, two-pass scan). The as-processed surface initially displayed complete wettability (water contact angle, CA ≈ 0°), consistent with freshly ablated metal behavior. Upon 30 days of ambient air ageing, the CA climbed to 154.5 ± 1.5° with a sliding angle of 4.5 ± 1.1°, establishing a pronounced superhydrophobic character. X-ray photoelectron spectroscopy (XPS) revealed that air exposure drove the formation of a low-surface-energy silica overlayer on the laser-structured surface, progressively shifting the wetting state from the Wenzel to the Cassie–Baxter regime. Scanning electron microscopy (SEM) confirmed a dual-scale rough texture comprising macro-scale groove channels (width: 35–40 μm, depth: ~20 μm) densely decorated with re-solidified granules (0.8–5.2 μm diameter), capable of entrapping substantial air volumes beneath water droplets. Mechanical robustness testing under cyclic compression demonstrated a contact angle retention of ~98.9%, validating the structural integrity of the superhydrophobic state. The process requires no supplementary chemicals, is technically straightforward, and offers a scalable path for imparting water-repellent, low-adhesion, and self-cleaning functionality to aluminum alloy surfaces. fiber laser texturing aluminum alloy superhydrophobicity wettability control anti-adhesion Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9544139","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":630488479,"identity":"b6cf6546-eb2f-454e-adff-e7931338d6bd","order_by":0,"name":"Zhang Wei","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYDACCQjFwy//+ACYASIOPICJ49Mi2ZCWwHAApiWBCC0MBgdyDBgOwEQT8LhLfnbzs4df22xkJBvOfPz8oWKbDP+0ww+BtljI4dLCOOeYubFsWxoPP2PvZokDZ27zSNxOMwA5zBiXFmaJBDNpyW2HeSSbeTdIHGy7zWMgnQDWktiAQwubRPo3oJb/PAbHeB7/gGhJ/4BXC49Ejpnkx20HeAzO8LBBbcnBb4uERE6ZNOO/ZB7JGWxmFmfAfskpOJBggNsv8jPSt0n+OGNnzy/B/PhGRcVte/7Z6Zs/fKiowxli4CDgwRQzwKcBGNA/8MuPglEwCkbBSAcALNhYXpBadSEAAAAASUVORK5CYII=","orcid":"","institution":"Shenyang Ligong University","correspondingAuthor":true,"prefix":"","firstName":"Zhang","middleName":"","lastName":"Wei","suffix":""},{"id":630488480,"identity":"b817d529-a75a-4a21-ace3-516d281686db","order_by":1,"name":"Li Xiaoyu","email":"","orcid":"","institution":"Shenyang Ligong University","correspondingAuthor":false,"prefix":"","firstName":"Li","middleName":"","lastName":"Xiaoyu","suffix":""},{"id":630488481,"identity":"e9be36e0-741c-4c7d-b358-0e77d8a5e628","order_by":2,"name":"Wang meilin","email":"","orcid":"","institution":"Shenyang Ligong University","correspondingAuthor":false,"prefix":"","firstName":"Wang","middleName":"","lastName":"meilin","suffix":""},{"id":630488482,"identity":"76db16fc-b131-4dc2-823a-e7aae7cb5ccc","order_by":3,"name":"Chen Hao","email":"","orcid":"","institution":"Shenyang Ligong University","correspondingAuthor":false,"prefix":"","firstName":"Chen","middleName":"","lastName":"Hao","suffix":""}],"badges":[],"createdAt":"2026-04-27 15:58:30","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-9544139/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9544139/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108007502,"identity":"2b372973-e904-4859-8b31-e97030ae78b5","added_by":"auto","created_at":"2026-04-28 13:00:16","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":582375,"visible":true,"origin":"","legend":"","description":"","filename":"newsuperhydrophobicpaper.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9544139/v1_covered_0581986f-7142-47d4-ade0-8d24b14ec4d8.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eFrom Superhydrophilicity to Superhydrophobicity: Laser-Induced Wettability Control of 7075 Aluminum via Chemical-Free Surface Texting and Air Ageing\u003c/strong\u003e\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"fiber laser texturing, aluminum alloy, superhydrophobicity, wettability control, anti-adhesion","lastPublishedDoi":"10.21203/rs.3.rs-9544139/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9544139/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study presents a reagent-free route to engineer robust superhydrophobicity on 7075 aluminum alloy substrates through fiber laser surface texturing. 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